At balanced field length you legally must abort before V1 or go past V1 to be safe. If you don't do that you are not legal. However if logic says I have extra runway today and I have leeway then think about what is more important, being legal, or being safe. I have briefed many departures with cliffs at the end of the runway differently than departing with an obstacle. My most critical airport was Tegucigalpa, Honduras. It had a 4 ft fence and a 70 ft drop off at the end. How would you like to overshoot an abort on that short runway? Taca just did a demo on that one on landing.